Bone marrow mesenchymal stem cells are pluripotent in vivo stem cells, and they are known to differentiate into osteoblasts, adipocytes, cartilage and such. Recently, it is beginning to be reported that in patients with tissue damage such as cerebral infarction, administration of their own bone marrow mesenchymal stem cells can promote healing of the tissue damage. However, since bone marrow mesenchymal stem cells are scarce cells in the bone marrow, there is a limit to the amount that can be collected from a patient. Therefore, obtaining the amount of bone marrow mesenchymal stem cells necessary for treatment of a wide range of tissue damages is difficult. At present, the method of culturing the bone marrow mesenchymal stem cells for proliferation to secure the number of cells needed for treatment is adopted. However, it is very difficult to culture bone marrow mesenchymal stem cells while maintaining their undifferentiated state. Furthermore, there are many associated problems to be solved, such as viral and bacterial contamination and canceration of cells. Furthermore, the cost for culturing cells that are guaranteed with safety and quality is huge.
On the other hand, bone marrow mesenchymal stem cells have been known to have an effect of facilitating the healing of spinal cord injury as well. This is assumed to arise from differentiation of pluripotent bone marrow mesenchymal stem cells into nerve cells, and supply of components having an effect of improving tissue damage such as growth factors by bone marrow mesenchymal stem cells accumulated at the damaged tissues.